title: Physical activity, life events stress, cortisol, and DHEA: preliminary findings that physical activity may buffer against the negative effects of stress.
abstract: The present study examined the relationship between habitual physical activity, life events stress, the diurnal rhythms of cortisol and DHEA, and the cortisol:dehydroepiandrosterone (DHEA) ratio in older adults. Thirty-six participants aged ≥ 65 reported their habitual physical activity, and indicated if a particular event happened to them in the past year (stress incidence) and how stressful they perceived the event to be (stress severity). Older adults with higher stress severity demonstrated a significantly higher cortisol:DHEA ratio. Individuals with higher stress incidence scores and who did not participate in aerobic exercise had a significantly higher cortisol:DHEA ratio and flatter DHEA diurnal rhythm compared with those who regularly participated in aerobic exercise. In conclusion, life events stress may have a negative impact on the cortisol:DHEA ratio in older adults. Under conditions of high stress exposure, exercise may protect older adults from an increased cortisol:DHEA ratio and flatter DHEA diurnal rhythm.
authors.affiliation: School of Sport and Exercise Sciences, University of Birmingham, Birmingham, West Midlands, England, UK.
authors.forename: Jennifer L J
authors.initials: JL
authors.lastname: Heaney
authors.forename: Douglas
authors.initials: D
authors.lastname: Carroll
authors.forename: Anna C
authors.initials: AC
authors.lastname: Phillips
mesh_terms: D000368:Aged; D000375:Aging / Q000378:metabolism / Q000523:psychology; D002940:Circadian Rhythm / Q000502:physiology*; D003687:Dehydroepiandrosterone / Q000378:metabolism*; D015444:Exercise / Q000502:physiology / Q000523:psychology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008016:Life Change Events; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D065840:Protective Factors; D012463:Saliva / Q000378:metabolism; D013223:Statistics as Topic; D013315:Stress, Psychological / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control / Q000523:psychology
chemical_list: D003687:Dehydroepiandrosterone; D006854:Hydrocortisone